The invention relates to a cam follower for a high-pressure fuel pump or for a valve drive in each case of an internal combustion engine with quantity or quality regulation, having a cam roller which is accommodated in a pocket of the cam follower, which cam roller is mounted by means of its bore on a pin which is seated at the ends in receptacles of opposite walls of the pocket, the cam roller running with its end sides directly in front of said walls.
A cam follower of said type emerges from DE 10 2005 047 234 A1. Said cam follower is designed as a cup-shaped tappet and serves to exert a periodic loading on a pump piston of a fuel pump. A further cam follower is described in DE 103 54 683 A1. Said cam follower takes the form of a rocker arm and is used for exerting a loading on a gas exchange valve in a valve drive.
In each case one roller mounted on a pin serves as a cam opposing member. Said roller runs via its end sides, which are planar with the exception of a structurally necessary chamfer in the transition region to the bore and to an outer surface of the cam roller, against flat walls of the pocket. On account of tolerances and/or the unfavorable summing thereof, an edge region of the end side to the outer surface of the cam roller may come into contact, during operation, with the corresponding wall of the pocket. In addition to the wear in the region of direct contact, the cam roller is braked, which results in slippage in the bearing and at the cam contact area. It is attempted in the prior art to counteract the undesirably high wear by means of very high production accuracy, applied coatings and/or improved lubrication.